/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.io.kinesis;



import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStream;

import com.amazonaws.services.kinesis.model.ShardIteratorType;

import org.joda.time.Instant;



import java.io.Serializable;

import java.util.Objects;



import static com.bff.gaia.unified.vendor.guava.com.google.common.base.Preconditions.checkNotNull;



/**

 * Denotes a point at which the reader should start reading from a Kinesis stream. It can be

 * expressed either as an {@link InitialPositionInStream} enum constant or a timestamp, in which

 * case the reader will start reading at the specified point in time.

 */

class StartingPoint implements Serializable {



  private final InitialPositionInStream position;

  private final Instant timestamp;



  public StartingPoint(InitialPositionInStream position) {

    this.position = checkNotNull(position, "position");

    this.timestamp = null;

  }



  public StartingPoint(Instant timestamp) {

    this.timestamp = checkNotNull(timestamp, "timestamp");

    this.position = null;

  }



  public InitialPositionInStream getPosition() {

    return position;

  }



  public String getPositionName() {

    return position != null ? position.name() : ShardIteratorType.AT_TIMESTAMP.name();

  }



  public Instant getTimestamp() {

    return timestamp != null ? timestamp : null;

  }



  @Override

  public boolean equals(Object o) {

    if (this == o) {

      return true;

    }

    if (o == null || getClass() != o.getClass()) {

      return false;

    }

    StartingPoint that = (StartingPoint) o;

    return position == that.position && Objects.equals(timestamp, that.timestamp);

  }



  @Override

  public int hashCode() {

    return Objects.hash(position, timestamp);

  }



  @Override

  public String toString() {

    if (timestamp == null) {

      return position.toString();

    } else {

      return "Starting at timestamp " + timestamp;

    }

  }

}